Then the Lord spoke to Moses, saying, “Speak to the sons of Israel, saying, ‘If a person sins unintentionally in any of the things which the Lord has commanded not to be done, and commits any of them, if the anointed priest sins so as to bring guilt on the people, then let him offer to the Lord a bull without defect as a sin offering for the sin he has committed. He shall bring the bull to the doorway of the tent of meeting before the Lord , and he shall lay his hand on the head of the bull and slay the bull before the Lord . Then the anointed priest is to take some of the blood of the bull and bring it to the tent of meeting, and the priest shall dip his finger in the blood and sprinkle some of the blood seven times before the Lord , in front of the veil of the sanctuary. The priest shall also put some of the blood on the horns of the altar of fragrant incense which is before the Lord in the tent of meeting; and all the blood of the bull he shall pour out at the base of the altar of burnt offering which is at the doorway of the tent of meeting. He shall remove from it all the fat of the bull of the sin offering: the fat that covers the entrails, and all the fat which is on the entrails, and the two kidneys with the fat that is on them, which is on the loins, and the lobe of the liver, which he shall remove with the kidneys (just as it is removed from the ox of the sacrifice of peace offerings), and the priest is to offer them up in smoke on the altar of burnt offering. But the hide of the bull and all its flesh with its head and its legs and its entrails and its refuse, that is, all the rest of the bull, he is to bring out to a clean place outside the camp where the ashes are poured out, and burn it on wood with fire; where the ashes are poured out it shall be burned.
Leviticus 4:1-12 NASB
http://bible.com/100/lev.4.1-12.NASB
One of the notes in my Bible makes an interesting observation. Unintentional sin, while it is not on purpose or born out of open rebellion against God, is still sin. It is as capable of separating us from our God as any other sin. We need to be mindful of this and, as Paul told the Corinthians, examine our hearts continually and ask God if there be any wicked way in us. Let no sin, no matter how small, separate you from God. Confess it to God and ask for His forgiveness.